17. The last time we met each other was one year ago. 
18. The date of meeting will have to be changed again. 
19. The lessons were being written by the students. 
20. English is spoken all over the world. 
21. Has my bedroom been decorated?
22. That book was bought yesterday.

15. It was not until he was 10 that he knew how to read. 
16. She has worked as an actress for ten years. 
17. The last time we met each other was one year ago. 
18. The date of meeting will have to be changed again. 
19. The lessons were being written by the students. 
20. English is spoken all over the world
11. If we had had a map, we wouldn't have got lost. 
12. If he doesn't tell lies, people will like him. 
13. If I had known how to difficult it had been, I wouldn't have taken the job. 
14. It was not until yesterday that he sent the letter. 
.
21. Has my bedroom been decorated?
22. That book was bought yesterday.